Electrochromatography, chromatographic

This overview concerns the new chromatographic method - capillary electrochromatography (CEC) - that is recently receiving remarkable attention. The principles of this method based on a combination of electroosmotic flow and analyte-stationary phase interactions, CEC instrumentation, capillary column technology, separation conditions, and examples of a variety of applications are discussed in detail. 

Electromigration and chromatographic methods developed as separate techniques over many decades. Today both methods have converged into a single approach capillary electrochromatography. The approach is still under development, but has already demonstrated to be very promising. From the current findings and the overall CE expertise that was... 

Freitag, R. (2004). Comparison of the chromatographic behavior of monolithic capillary columns in capillary electrochromatography and nano-high-performance liquid chromatography. J. Chromatogr. A 1033, 267-273. 

Allen, D., and El Rassl, Z. (2004). Capillary electrochromatography with monolithic silica columns III. Preparation of hydrophilic silica monoliths having surface-bound cyano groups chromatographic characterization and application to the separation of carbohydrates, nucleosides, nucleic acid bases and other neutral polar species.. Chromatogr. A 1029, 239—247. 

The majority of papers written on MIPs deal with their testing or application in a chromatographic, solid-phase extraction (SPE), or capillary electrochromatography (CEC) system. Many excellent reviews have been written in the last decade on such MIP systems [1-29]. These reviews discuss the large variety of templates used, the polymerization strategies, the formats of the separation system, and the optimization of the separation process. In earlier years there were only very few applications on real samples to be reported. This has changed recently and reviews are also becoming available on this topic [30]. 

HPLC-UV-NMR can now be considered to be a routine analytical technique for pharmaceutical mixture analysis and for many studies in the biomedical field. HPLC-UV-NMR-MS is becoming more routine with a considerable number of systems now installed worldwide, but the chromatographic solvent systems are limited to those compatible with both NMR spectroscopy and mass spectrometry. The increased use of HPLC-UV-IR-NMR-MS is possible, but it is unlikely to become widespread, and the solvent problems are more complex. The future holds the promise of new technical advances to improve efficiency, and to enhance routine operation. These approaches include the use of small-scale separations, such as capillary electrochromatography, greater automation, and higher sensitivity and lower NMR detection limits through the use of NMR detectors cooled to cryogenic temperatures. 

Slentz et al. [23] described nanocapillary electrochromatography on collocated monolithic support structures (COMOSS) molded in PDMS. The authors fabricated a chromatographic channel by molding COMOSS directly. In addition, the ability to separate biological samples such as peptides from a... 

Electrochromatography was first demonstrated in the open-tubular microfluidic channel coated with octadecylsilane (ODS) as the chromatographic stationary phase. EOF was used as the pumping system within the 5.6-pm-deep and 66-pm-wide channels. Plate heights of 5.0—44.8 pm were achieved for three cou-marin dyes [112]. Open-channel CEC separation was achieved using a stationary phase of octadecyltrimethoxysilane [148], CEC separation of some PAHs has also been carried out on a Pyrex chip with a thin film of C8 stationary phase formed using a sol-gel process [338],... 

The potential influence of the nature of the driving force on the chromatographic selectivity for neutral molecules has been investigated using CEC, pLC and pressurised flow electrochromatography. The comparison was performed on the same prototype instrument and the same column to eliminate all other possible influences... 

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